In the context of today, sure; but in the era they were added, they (sort of) made sense:
2004/5: - BC to ACC... that was an era of TV markets reigning supreme in rights deals; BC nominally opened up the Boston market to the ACC. There really weren't alternatives, as UConn was only a few years into its FBS journey, and Miami was calling the shots of who it wanted to bring along
2011 - Syracuse to ACC... still a TV market era and had been initially invited to the ACC back in 2004 before political maneuvering put Virginia Tech into their place; was envisioned to open up the NYC market to the ACC. UConn was the preferred partner with Syracuse and were, reportedly replaced with Pitt with BC's urging and the collective yawn from the rest of the league, given the money offered was the same as the Syracuse-UConn pairing.
2021 - Cincinnati & UCF to the Big XII... the Big XII was imploding with Texas & Oklahoma leaving they needed to replace them, plus add a few more teams to increase inventory to maintain their TV deal. At the time UCF had recently had its run with an undefeated and one-loss season, while Cincinnati was headed to the playoffs after a narrow miss the year before. As the Pac-12 was still seemingly healthy they got the nod; would they have if the Pac-12 implosion happened at the same time? Probably not. They were in the right place (winning programs in the AAC) at the right time (when the Big XII was desperate). UConn has hit rock bottom in football at this point & just had made the move to leave it's all sports home for a non-football primary conference. It's the right move for UConn; but UConn is unique and to those more traditional schools it's a sign that UConn isn't serious about football.
To be the right team at the right time, UConn needs to continue to demonstrate competence and show the investment that they are serious in football. Continued success from the basketball programs is a nice sweetener as conferences start to look to maximize revenue there, particularly in light of a dearth of programs that would increase revenue by a full share on their own.